摘要
无网格动力法中质量矩阵的构造对计算结果的精度有着重要影响。本文就无网格动力法中质量矩阵的构造方法,给出了一致质量矩阵和集中质量矩阵的数学表达式,运用MATLAB软件编制了基于不同质量矩阵的无网格动力法计算程序,对无约束矩形板不同质量矩阵构造下的频率和振型进行了对比计算。结果表明:采用集中质量矩阵时,结果受节点划分的影响较大,只有节点划分足够密集时,结果才趋于精确值;而采用一致质量矩阵时,结果受节点划分的影响较小,说明了一致质量矩阵在无网格动力法质量矩阵构造中的优越性。
The structure of the mass matrix in the meshless dynamic method has important influence on the accuracy of the calculation results.This paper presents the method for construction of mass matrix in the meshless dynamic method.The MATLAB software is used to compile the meshless dynamic calculation program based on the different mass matrix.The frequency and mode of the structure of the different mass matrices of the unconstrained rectangular plate are calculated and compared.The results show that the lumped mass matrix and the affected node partition is large,and that only when the node is dense enough,the result tends to the exact value;the consistent mass matrix being adopted,the affected node partition is small,showing the superiority of the consistent mass matrix in grid power quality in matrix structure.
引文
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